Stephen Hawking
Stephen Hawking was an English theoretical physicist and cosmologist who's considered one of the most brilliant scientists since Albert Einstein. In addition to making huge contributions to physics, Hawking strove to share his discoveries with the general public, and his book "A Brief History of Time" was a best seller. Moreover, Hawking did most of his research while battling amyotrophic lateral sclerosis, which makes his accomplishments even more remarkable.
In 'Brief Answers to Big Questions', completed after Hawking's death (from his speeches, interviews, essays, notes and lectures), the gifted scientist responds to a number of queries that are relevant to our time.
However it's Hawking's QUESTIONS about relativity and quantum mechanics that will resonate going forward. In the introduction to this book, American theoretical physicist and Nobel laureate Kip Thorne writes: "Newton gave us answers, Hawking gave us questions. And Hawking's questions themselves keep on giving, generating breakthroughs decades later. When ultimately we master the quantum gravity laws and comprehend fully the birth of our universe it may largely be by standing on the shoulders of Hawking."
Kip Thorne is an American theoretical physicist and Nobel laureate, known for his contributions in gravitational physics and astrophysics.
One of Hawking's most important contributions to science was his discovery of 'Hawking Radiation', composed of particles emitted from black holes. It was once thought that NOTHING could escape from a black hole, but this isn't the case. The idea goes as follows: Quantum mechanics implies that space is filled with particles and anti-particles - which are constantly appearing in pairs, separating, them coming together again and annihilating each other. In the presence of a black hole one member of the pair may fall into the black hole, leaving the other member without a partner to engage in mutual annihilation. This particle (or anti-particle) may escape as 'radiation' from the black hole.
Sketches depicting Hawking Radiation
Scientists speculate that, unless a black hole gains mass (by engulfing other objects), it will eventually vanish.
*****
In this book Hawking answers questions he's been asked over the years. I'll give a brief synopsis of his responses, and leave you to read the book if you want more information.
- Is there a God?
No. Everything can be explained by the laws of nature. Matter and energy and space were spontaneously created by the Big Bang.
- What came before the Big Bang?
This is a meaningless question because there was no 'before' the Big Bang. Time (actually spacetime) was created BY the Big Bang. It's like asking 'what is south of the South Pole?'
Spacetime (which is warped by the presence of solid matter) was formed by the Big Bang
There's no 'south' of the South Pole
- Is there other intelligent life in the universe?
We don't know (yet) but Hawking likes to think there are other forms of intelligent life out there. They just haven't contacted Earth....perhaps because they're too far away.
In any case, meeting an advanced civilization would be unadvisable (for us). Remember European settlers and American Indians? If aliens came here it would be like the film 'Independence Day.'
- Can we predict the future?
No. The Heisenberg Uncertainty Principle dictates that we can't know both the position and momentum of a particle at the same instant. Thus we can't predict what will happen to a particle (or things made of particles) at a future time. Hawking observes: “No matter how powerful a computer you have, if you put lousy data in you will get lousy predictions out.”
- What is inside a black hole?
A black hole - which is single point of infinite density - is a star that's exhausted its nuclear fuel and collapsed.....but no one REALLY knows what's inside.
- Is time travel possible?
Theoretically yes. If spacetime was warped enough to form a loop, time travel would be possible. However, it time travel WAS possible, someone from the future would probably have come back to visit us already.
In 2009, Hawking held a party for time travelers in his college at Cambridge, for a film about time travel. No one came.😊
- Will we survive on Earth?
Not forever. Nuclear war is a dire threat and there will be a meteorite strike at some point. Moreover, global warming is likely to make Earth uninhabitable, since our climate could become like that of Venus - boiling hot and raining sulfuric acid."
Hawking notes: "One way or another, I regard it as almost inevitable that either a nuclear confrontation or environmental catastrophe will cripple the Earth at some point in the next 1,000 years which, as geological time goes, is the mere blink of an eye. By then I hope and believe that our ingenious race will have found a way to slip the surly bonds of Earth and will, therefore, survive the disaster. The same of course may not be possible for the millions of other species that inhabit the Earth, and that will be on our conscience as a race."
- Should we colonize space?
Yes. In order to survive long term, humans need to colonize other planets. This won't be cheap. Hawking helped initiate a research and engineering project called 'Breakthrough Starshot", which strives to develop spacecraft capable of reaching the star system Alpha Centauri - which is 4.37 light-years (about 26 trillion miles) away.
Hawking believes that in the next hundred years humans will be able to travel to the inner planets of the solar system and in 500 years we will have visited the nearest stars.
Breakthrough Starshot
- What are the prospects that scientists will unite Einstein's theory of relativity and quantum theory to achieve a complete theory of the laws of the universe?
This will happen within the next millennium.
- Will human genetic engineering occur?
Yes. If scientists learn how to do something, SOMEONE will do it.....even if it's illegal.
- Will artificial intelligence outsmart us?
Yes. Computers are likely to overtake human intelligence in the next 100 years. Thus we need to ensure that computers have goals in line with ours. Just to be safe, robotic designs should always incorporate a 'kill switch.'
- What world changing idea would you like to see implemented by humanity?
The development of fusion power to give an unlimited supply of clean energy. It would be an inexhaustible supply of energy without pollution or global warming.
*****
Despite everything, Hawking was an optimistic soul. He advocates that we should: “Be brave, be curious, be determined, overcome the odds. It can be done."
I found the book interesting and informative and would recommend it to people interested in Hawking's view of the 'big questions.'
Rating: 4 stars
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